1. Technical Field
The present invention generally relates to a keyboard scanning circuit, a keyboard and a scanning method thereof and, more particularly to, a keyboard scanning circuit, a keyboard and a scanning method thereof capable of preventing ghost keys.
2. Description of Related Art
The keyboard scanning circuit in an existing keyboard utilizes a scanning matrix composed of scanning lines and sensing lines crisscrossed. A key is provided corresponding to where one of the scanning lines and one of the sensing lines intersects. However, ghost keys are inevitable on such a keyboard scanning circuit. To date, there have been some solutions to key ghosting, for example, by adding a diode to each key or enhancing the I/O capability of a microprocessor to augment the scanning matrix.